1. Field of the Invention
The present invention relates to a method of matching transactions performed by a plurality of clients connected to a distributed network system through a network server.
This application is based on patent application No. Hei 09-187401 filed in Japan, the content of which is incorporated herein by reference.
2. Description of the Related Art
In a distributed network system connected to a plurality of clients sharing a common network server, when transactions involving different commands are requested by each client, different approaches have been used to respond to such a situation.
First conventional method which is a generally accepted approach in a distributed network system, can execute a plurality of transactions in parallel, by locking those preceding updating transactions of a common data base, and other transactions requesting inquiry or updating of the common data base are made to wait, so that the transactions calling for the common data base can be serialized chronologically.
In a second conventional method disclosed in a Japanese Patent Application, First Publication, Sho. 63-310042, when a plurality of clients issue commands of different semantics to a common data base, a consultation process is invoked so that the different clients can cooperate to arrive at a correct operational step.
In such methods of matching conflicting transactions, one of the problems is that the method can only offer a uniform mediation solution. The reason is that, in the first method, all the conflicting transactions are always serialized regardless of the contents of semantics conflicts. In the second method, mediation of conflicting transactions is carried out by consultations regardless of the contents of semantics conflicts.
Further problem in the second method is that for each conflicting transaction, a consulting step must always be carried out among the clients so that, if the cooperative step is being carried out on-line, the processes are frequently interrupted and become quite cumbersome.